Fix bearer token support

lib/image_registry/client.rb

@@ -19,7 +19,7 @@ module ImageRegistry
         if options[:user] && options[:password]
           builder.request(:basic_auth, options[:user].to_s, options[:password].to_s)
         elsif options[:token]
-          builder.request(:authentication, :Bearer, options[:token].to_s)
+          builder.request(:authorization, :bearer, options[:token].to_s)
         end
 
         builder.adapter :net_http

lib/image_registry/repository.rb

@@ -25,7 +25,7 @@ module ImageRegistry
 
     def tags
       return @tags if defined?(@tags)
-      return unless manifest && manifest['tags']
+      return [] unless manifest && manifest['tags']
       @tags = manifest['tags'].map do |tag|
         ImageRegistry::Tag.new(self, tag)
       end